Improvement in astronomical clocks or cosmochronotropes



5 Sheet s-Sheet 1.

- J. P. SARRATT.

Astronomical Clock 0r Oosmoohronotrope.

Patented Sept. 30,1879.

5 Sheets-Sheet 2,

J. F. SARRATT; Astronomical Clo-0k or Cosmochronotrope.

Patentd Sept. 30,1879.

wk 2:; u.

5 Sheet sP-Sheet 3.

, J. F. SARRATT. Astronomical Clock or Gosmoohronotrope. No. 220,036.Patented Sept. 30,1879.

K PHurmumoempnzn, WASHINGTON o c,

5 Sheets-Sheet,4.

J. F. SARRATT. Astronomical Clock or Gosmoohronotrope.

Patented Sept. 30,1879.

N.PETER$, PHOTO-LITHOGRAPHER, WASHINGTON, D 0.

5 Sheet s-Sheet 5.

J. I. SARRATT. Astronomical Clock or Cosmoohronotrope.

No. 220,036. Patented Sept. 30,1879.

UNITED STATES PATENT QFFICE.

JAMES F. SARRATT, OF STEUBENVILLE, OHIO.

IMPROVEMENT lN ASTRONOMICAL CLOCKS 0R COSMOCHRONOTROPES.

Specification forming part of Letters Patent N 0. 220,036, datedSeptember 30, 1879; application filed July 23, 1879.

To all whom it may concern:

Be it known that I, JAMEs F. SARRATT, of Steubenville, in the county ofJefi'erson and State of Ohio, have invented a new and useful Improvementin Astronomical Clocks or Oosmochronotropes; and I do hereby declare thefollowing to be a full, clear, and exact description thereof, referencebeing had to the accompanying drawings, forming part of thisspecification, in which- Figure 1 is a front elevation of my improvedheliotellus clock or cosmochronotrope. Fig. 2 is a side elevation. Fig.3 is a rear elevation. Fig. 4 is a top view. Fig. 5 is a plan View fromthe under side of the gearing which operates two watch movements,indicating mean time and the suns right ascension. Fig. 6 is a sectionaldrawing of the device by which the clock is detached from the rest ofthe apparatus. Fig. 7 shows a part of the equatorial circle.

In the several figures letters of reference denote the same parts.

My improved apparatus is a combination of astronomical clock andheliotellus, and is designed to illustrate and exhibit, first, therelative position of the sun and earth on each day of. the year; second,the right ascension and declination of the sun on each day of the year;third, mean time at any two places on the earths surface; fourth, thelength of day and night at any place and on any day of the year; fifth,the equation of time for any day of the year; sixth, the portion of theearths surface enlightened by the sun at any given time; and, seventh,the portion of time that the sun is north or south of the equator duringthe year.

Furthermore, my apparatus is so constructed that if kept wound up andallowed to run without interruption, it exhibits the relative positionof the earth and sun at all times; or if it be required to use theapparatus for the purposes ofillustration in teaching astronomy, theconnection of the spheres representing the earth and sun, with theclockwork which gives them motion, may be severed, and then theapparatus may be set in any desired position so as to work the severalproblems before referred to.

It will be unnecessary in this specification to explain in detail therelative motions of the sun and earth, or to explain the differencebetween mean timc, sidereal time, and apparent time, or the cause of thedifference between mean solar time and apparent solar time, or why theearths average velocity from the vernal to the autumnal equinox isslower than her average velocity from the autumnal equinox back to thevernal equinox, causing it to continue about eight days longer on thenorth side of the equator in summer than it does on the south side inwinter, as these matters will be found explained in any treatise onastronomy. Suffice it therefore to say that these variations areexhibited in my apparatus, the construction of which I shall proceed toexplain 5 and after doing so I shall give a few illustrations of itspractical operation.

In the several drawings, A is a clock, of any desired construction,operated by spring or weights, as may be preferred, and regulated eitherby spring-balance or pendulum, to show true, mean, or clock time. Thisclock furnishes the motive power of the whole apparatus, and is providedwith the necessary wheels and es capements so that the hour-han d shallperform one circuit around the dial in exactly twelve hours, and theminute-hand in exactly one hour'of mean time. It may also he providedwith a graduated circle and hand to indicate seconds of time.- Therebeing nothing peculiar about the clock itself, it needs no furtherdescription.

Attached to the rear of the clock-frame, and in line with the shaft ofthe minute-hand of the clock, is a stationary shaft, a, which serves asa bearing for the large cog-wheel, 1, of two hundred and nineteen cogs,turning freely thereon, and in rear of the cog-wheel l, and turning onthe same shaft a, is a smaller cogwheel, 2, of fifty-four cogs, which isconnected with the large cog-wheel, 1, so as to move with it and revolvein the same time. The large cogwheel, 1, receives its motion directlyfrom the gearing of the clock by means of two cogwheels, 3 4, on thesame shaft, and each having thirty-six cogs, one meshing into the largecog-wheel, 1, and the other into the cog-wheel 5 attached to the shaftwhich carries the spring or prime motor of the clock. Of course therelative number of cogs in the gear-wheels 1, 2, 8, and 4 will be suchin relation to the cogwheel 5 of the clock as to give the proper time ofrevolution of the large cog-wheel, 1; but the actual number ofcog-wheels will depend upon the number of cogs and time of revolution ofthe clock-wheel 5, from which the motion is derived.

The number of cogs in the several wheels of my apparatus maybe variedfrom that stated in this specification, but must be such as to give therelative speed of motion to the main parts of my apparatus, as ishereinafter stated.

The small cog-wheel, 2, gears into a larger cog-wheel, 6, of sixty'fivecogs, which is attached to a bracket, I), connected by arms 0 c with theclock-frame.

()n the same shaft as the cog-wheel 6, and in the rear of it, is anothercog-wheel, 7, having seventy cogs, which revolves loosely on its shaft.This cog-wheel 7 may be connected or disconnected at pleasure with orfrom its companion wheel 6 by means of a pin, d, which is passed throughthe face of the cog-wheel 7 and enters a corresponding notch or hole inthe face of the cog-wheel 6. When this pin (7. is drawn so far out asnot to takeinto the cog wheel 6, as shown in Fig. 6, the clock-work isdisconnected from the rest of the apparatus, which then ceases to haveany automatic motion.

The cog-wheel 7 has beveled gearing, which meshes into anotherbevel-wheel, 8, having seventy cogs, which is supported on the upperpart of the bracket 1) in an inclined position, at an angle of abouttwenty-three and a half degrees to a horizontal plane, being the angleof inclination of the axis of the earth to the plane of the ecliptic, myapparatus being constructed with the plane of ecliptic horizontal.

Attached to the inclined bevel-wheel S, and above it, is a cog-wheel, 9,similarly inclined, and having seventy-two cogs, which meshes into apinion, 10, rigidly attached to a vertical shaft, 0, the lower end ofwhich has its bearing in the bracket 1), and the upper end its bearingby passing through the upper bracket j, which bracket is also attachedto the clock-frame.

The pinion 10 has seventeen cogs, which are so inclined from a verticalline as to mesh into the teeth of the inclined cog-wheel 9.

The upper endof the shaft 0 of the pinion 10 passes up through the upperbracket,f, and is attached to one of the wheels 9 (say, the fusee-wheel)of the watch-movement B.

By means of the gearing already described the cog-wheels S and 9 (whichare attached to gether and have the same movement) make one revolutionin twenty-four hours, mean or clock time, and the vertical shaft e,which gives movementto the works of the watch B, causes the watch B tokeep mean clock time. By means of this watch, which moves in unison withthe works of the clock A, the mean time at two different places may beindicated-as, for instance, the clock A being set at mean time of theplace where my instrument is used, the watch B may be set at Greenwichtime, which is most commonly used in astronomical calculations.

The watch-movement B is of ordinary construction, excepting that thereis no mainspring nor escapement, as these are rendered unnecessary bythe fact that the watch receives its motion exclusively from the clock.A by means of the shaft 0, and is isochronous with it.

The shaft of the cog-wheel 9 is a hollow sleeve, 2', which receives theshaft h, to which the globe E is rigidly attached.

The globe E represents the earth, and the shaft h its imaginary axis,entering the globe at its south pole, and is accordingly inclined at anangle of twenty-three and a half degrees from a vertical position, thatbeing about the angle of inclination of the equator to the ecliptic.

The shaft 71, is secured to the sleeve 1' by a set-screw, i, so that bytightening or loosening this set-screw the shaft h is attached to ordetached from the cog-wheel 9. When so detached the shaft It may befreely rotated by hand and the a 'iparal us set in any desired position.

The gearing connecting the cog-wheel 9 with the clock A is such, asbefore described, that the globe E (representing the earth) revolvesfrom west to east once in every twenty-four hours of mean time. Theearth-shaft It has its upper bearing in the upper bracket, f, throughwhich it passes.

On the earth-shaft h, just below the upper bracket, f, is a pinion, 11,having ten cogs, which gears into a beveled idle-wheel, 12, also of tencogs, which is supported by the bracket f on its under side. Thisidle-wheel 12 gears into a cog-wheel, 13, of sixty cogs, which hasattached to its shaft a pinion, 14, of ten cogs, which gears into acog-wheel, 15, of sixty cogs. This cog-wheel15 is attached to the lowerend of a vertical shaft, It, which passes throiiigh the bracket f, andhas a shoulder bearing thereon.

The shaft 70 has two pinions, one, 16, at its upper end, (see Fig. 3,)having twenty-three cogs, and another, 17, lower down, having twenty-sixcogs, both of said pinions being attached to and revolving with thevertical shaft k.

Surrounding the globe E, and in the exact plane of the equator, is anannulus or equatorial circle, F, which is graduated to indicate thetwenty-four hours of the day, with subdivisions of the hours. At theouter periphery of this equatorial circle are cogs, two hundred andsixty-four in number, which gear into the pinion 17, of twenty-six cogs,and by which the equatorial circle is caused to rotate once for everythree hundred and sixty-five and onefourth revolutions of the globe E orearth, thus revolving around the earth once a year.

As is well known, the velocity of the earth is somewhat retarded whenpassing from her vernal equinox to her autumnal equinox, cansin g it totake eight days longer to accomplish that half of its orbit, whichvariation of motion also affects the equation of time, causing avariation between mean time or apparent or sun time.

In order to illustrate this variation in my apparatus, the two hundredand sixty-four cogs on the equatorial circle F are not quite uniformlydistributed around the equatorial circle, one-half of that circle,between thepoints marked with the hour VI on opposite sides of thecircle, having one hundred and thirty-four cogs, and the other half onlyone hundred and thirty cogs, the difference in size and distances of thecogs being so slight as not to interfere with the meshing of the pinion17, but effecting a retardation of motion of the equatorial circleduring half of its annual revolution, thus exhibiting the slowerapparent motion of the sun round the earth from the vernal to theautumnal equinox.

By means of the graduation-marks on the equatorial circle, whichindicate the twentyfour hours and their subdivisions, being uniformlyspaced around the equatorial ciicle, while the cog-wheels at theperiphery are not uniformly spaced, as just described, the equation oftime is indicated, being the difference between apparent time and meantime on every day of the year, excepting on the four days when mean timeand solar time are alike.

The equatorial circle F is supported in its inclined position coincidentwith the plane of the equator, and yet left free to be rotated, asbefore described, by resting loosely upon a fixed annulus, l, which issupported by a prop, m, attached to the clock-frame in front, and by astandard, a, rising from thebracket f in the rear.

The standard at extends upward to a point above the top of the globe Ein the rear. Another standard, 0, forming a vertical, or nearlyvertical, extension of the inclined prop 122, also rises to the sameheight in front. At the top of these standards a and 0, and rigidlyattached thereto, is an annulus, p, which is placed in a horizontalposition, so as to preserve the proper relative angle to the axis of theearth. This annulus 19 has a circular depression all around, near, andextending to its periphery, in which rests the sun-wheel G, at theperiphery of which are two hundred and thirty-four cogs, which mesh intothe cogs of the pinion 16 at top of the upright shaft k, and cause it torevolve in a horizonal plane, its axis of rotation being at right anglesto the plane of the ecliptic, and at an angle of twenty-three and a halfdegrees to the axis of rotation of the equatorial circle F. The pinion16 having twenty-three cogs causes the sun-wheel to make one completerevolution in three hundred and sixty-five and one-fourth days, or oncefor every three hundred and sixty-five and one-fourth revolutions of theearth E on its axis.

As the sun-wheel G carries a sphere, S, representing the sun and itsapparent motion around the earth, it is necessary that the motion of thewheel G should be such as to correspond to the varying time or velocityof motion of the earth around the sun, before referred to; and this isaccomplished in the same manner as before described in relation to therevolution of the equatorial circle Fthat is to say, the two hundred andthirty-four co s or teeth on the sun-wheel G are unequally distributedaround its periphery, one-half from the point marked a to the pointmarked 0;, diametrically opposite, having one hundred and twenty cogs,and the other semi-circumference, from a" to 00, having only one hundredand fourteen cogs. The half of the sunwvheel G having thelarger numberof cogs is placed so as to coincide with the half of the equatorialcircle F which has the greater number of cogs, so that the revolutionsof the sun-wheel G and equatorial circle F may be coincident in time andin relative position.

Tne sun-wheel G has a cross-piece, (1, passin g diametrically across it,to which is rigidly attached a sleeve, r, at the center of the wheel G.On top of the sleeve 1' is placed a magnetic compass, 2.

To one side of the center of the sun-wheel G, on the cross-piece q, isfixed a sleeve, t, through which passes horizontally a rod, to, fastenedto sleeve 2 by a set-screw, 8. At the outer extremity of the rod t isanother sleeve, t, furnished with a set-screw, 8, through which sleeve25 passes a vertical rod, a, at the lower extremity of which is a ballor sphere, S, representing the sun. WVhen the apparatus is sufficientlylarge to enable me to do so, I use in place of the ball S a globe ofglass, preferably frosted, containing a small lamp, to represent thesun.

The horizontal arm a is further held in its position, which is that of aradius of the circle of the sun-wheel G, by a pin, Q7, which passesthrough the arm a and enters the face of the sun-wheel G.

The length of the vertical rod to is such that the center of the sphereS, or sun, is in the same horizontal plane as the center of the globe E,representing the earth. Thus, by means of the revolution of thesun-wheel G on its axis in three hundred and sixty-five and one-fourthdays, or once for each three hundred and sixty-five and one-fourthrevolutions of the earth on its axis, the sun-sphere S is caused torevolve around the earth E according to its apparent motion from east towest, which, for all the purposes of my apparatus, serves the samepurpose as if the earth-globe E were caused to perform an annualrevolution around the sun S.

A short rod, to, is inserted into the sleeve 4' at the center of thesun-wheel G, and attached thereto by a set-screw, 8. To the lowerextremity of this rod 20 is attached a circular strip of metal, 7 whichextends nearly around. the earth-globe E from the point near its northpole, and parallel to and nearly touching its surface, at right anglesto the plane of the ecliptic, thus dividing the globe into two equalparts. Both arms of this circular strip y occupy a vertical plane atright angles to the horizontal arm a which carries the sun S, and asthis circular strip y revolves around the globe E with the sun-wheel, itserves, in every position of the globe E, to indicate that partof theearths surface which is enlightened by the rays of the sun, and to markthe line dividin g day and night.

As it is necessary that this circular strip y should preserve at alltimes a vertical position in a plane at right angles to a line drawnfrom the center of the sun S to the center of the earth E, it is kept insuch position by two pins, a a, attached to and projecting inward fromopposite sides of the equatorial circle F, and which pass into thenarrow space between the circular strip y and guide-strips I), one ofwhich is attached to each side of the circular strip 3 The circularstrip y is further kept in position by a semicircular are of wire, 0,which half surrounds the earth-globe E in the exact plane of theecliptic on that side which is toward the sun S. This are 0 serves toindicate on the surface of the earth the apparent path of the sunbetween the tropics of Cancer and Capricorn, and shows at what pointsthe sun is vertical at any given time.

The revolution of the sun-wheel Gr carries with it the sun S, which isthus caused to make an annual revolution around the globe E,representing its apparent motion around the earth, which, by the gearingalready described, is completed, if the apparatus is run by the clock A,in an actual period of three hundred and sixty-five days and one-fourth;or if the apparatus is turned by hand the sun S revolves once round theearth E for each three hundred and sixty-five and one-fourth revolutionsof the globe E on its own axis.

Supported on the annulus p, which projects slightly beyond thecircumference of sun wheel G for that purpose, is a g aduatedecliptic-circle, D, which is stationary. This circle is divided intoequal spaces for the days of theyear, with larger divisions for themonths, which are marked thereon. This circle is preferably made ofmetal of different color from the sun-wheel G and zodiac-circle H forthe purpose of distinction. The zodiac circle H is also supported by theannulus p, and is placedimmediately outside of the ecliptic-circle I),and, likeit,1s stationary. The zodiac-circle H is graduated into twelvespaces by radial lines, which, by their coincidence with the graduationson the ecliptic'eircle D, indicate the day on which the sun enterscachsign of the zodiac.

011 the horizontal arm a, which carries the sun-sphere S, is attached asleeve, (1, by means of a set-screw, c, projecting from which sleeve dis a pointer, i, which, as the sun-wheel G revolves, points to the dayson the stationary ecliptic-circle D, and points to the day of the month,and gives the exact relative position of the earth and sun on each dayof the year.

The watch-movement 1-3, which indicates mean or clock time, is run, asbefore described, by the shaft 0, which receives its motion from theclock A by intermediate gearing.

. ()n the same bracket f, and alongside of the watclTi-movement B, isplaced a second watchmovement, 0, which indicates the right ascension ofthe sun, and receives the requisite motion for that purpose as follows:At the lower extremity of the vertical shaft It, and under the bracketf, is a cog-wheel, 15, before men tioned, of sixty cogs. Immediatelyabove this cog-wheel l5, and secured to the same shaft It, so as toreceive motion therefrom, is a cogwheel, 18, of fifty nine cogs, whichgears through an idler, 19, having twenty-five cogs, with a cog-wheel,20, also of twenty-five cogs, attached to the spindle of the minute-handof the watch-movement O. This watch 0 has the usual wheels intermediatebetween the minute-hand wheel and the seconds-wheel and hour-wheel, soas to communicate the proper relative motion of the hour, minute, andseconds hands of the watch 0.

The gearing which runs the watch-move ment 0 is so proportioned, asbefore described, as to cause its minute-hand to traverse its dial oncein the one twentyfourth part of a year, while the hour-hand makes onecomplete revolution in one'half of a year, and the seconds-handtraverses its dial sixty times for each revolution of the minute-hand;or, in other words, this watch-movement runs so that its hour-handtraverses its dial twice for every complete revolution of the sun-sphereS around the earth-globe E. By this arrangement the hands of thewatch-movement 0 show in hours, minutes, and seconds the right ascensionof the sun on every day of the year.

In order to indicate the declination of the sun and as certain latitudesa thin metallic strip, 76, is stretched from one pole to the other ofthe terrestrial globe E, so that one edge of the strip shall coincidewith the meridian, and is pivoted to the axis of the globe at each pole,so as to be capable of being turned and set at any required position.The edge of this strip It which lies in line of the meridian isgraduated to indicate degrees and smaller di visions of the polarcircumference ofthe earth, so that being turned around until thegraduated edge touches any city or other point on the earths surface,the latitude of such place may be read on the meridian-strip. Thegraduations run, of course, from zero at the equator to ninety degreesat each pole. The suns declination is indicated by the graduationmarksbetween the tropical circles.

I have thus described the mechanism of my improved apparatus as shown inthe drawings. 7

It is obvious that the utility of my machine is increased as its size isenlarged. In alarge machine, where the terrestrial globe is ofsufficient size to indicate with comparative accuracy the position ofplaces on the earths sur face, and where the ecliptic-circle D, theequatorial circle F, and the meridian-strip 7c can be minutely andaccurately graduated, and where the teeth of the wheels can be made ofsmaller size and greater number than is indicated in this specification,the operation will be more correct and the results more accurate.

Owing to the necessary smallness of the figures in the drawings, I havenot attemptedin all cases to show the number of teeth in the cogwheels,and, in some instancesas, for example, on the periphery of theequatorial circle I have not shown any cog-teeth at all. It will beunderstood, however, from the specification which wheels aregear-wheels, as well as the required relative number of teeth in theseveral wheels.

The uses of this apparatus 1- have described will be obvious to all whoare familiar with the elements of astronomical science; but in order tomake the operation and utility of my machine more apparent, I willproceed to describe the manner of working it and some of the uses towhich it is designed to be applied.

In order to use the clock, when it is designed to run automatically, itis necessary that it should be set and started correctly. In order to dothis, first loosen the set-screw which connects the axis h of theterrestrial globe with the gearing which is intermediate between theshaft h and the clockA. Then, by revolving the shaft h, turn thesun-wheel Gr until the pointer 93 on the arm a is over the mark on theecliptic-circle D, indicating the 21st day of j March, (the vernalequinox.) Then see that the zodiacal circle H is correctly placed,having the line between Aquarius and Pisces on the circle Hcorresponding with the date of 21st March on the ecliptic-circle D,because the sun enters Pisces (which is now the first constellation) atthat time. Then set the hour, minute, and seconds hands of thewatch-movement 0 at XII exactly. The apparatus thus adjusted is set forthe 21st March, when. the suns apparent right ascension and declinationare at zero. The hour XII on the equatorial circle should thencorrespond with. the point where the semicircular ecliptic are cintersects the equator on the terrestrial globe E.

When thus set rotate the sun-wheel G by turning the axis or shaft h, asbefore, until the pointer 13 on the arm a of the sunwheel arrives at thegrad nation-mark on the eclipticcircle D indicating the day on which orfor which the instrument is to be started or set, bringing theterrestrial globe E to rest with the meridian-line of the place wherethe instrument is used, or for which it is set, exactly in line with thehour XII, noon, on the equatorial circle F and directly facing the sunS. Then tighten the set-screw j, thus connecting the terrestrial globewith the clock A, and set the clock A at XII oclock, noon, plus or minusthe equation of time, or the difference between apparent time and meanor clock ti me, as the sun may be slow or fast, and set thewatch-movement B at mean Greenwich time, which will be faster or slowerthan the clock A, as the place where the instrument is set is east orwest of the meridian of Greenwich, allowing four minutes of time forevery degree of difference of longitude between the places. Then windand start the clock A, and if it is regulated to keep true clock-time,and be allowed to run without interruption, it will indicate on each daythe correct position of the earth in relation to the sun. The pointer 2"will mark on the ecliptic-circle D the month and day of the montl1,a11dthe position of the sun in relation to the zodiacal constellations, thetime at which the sun rises and sets on that day at the place for whichthe apparatus is set, the equation of time or time by apparent sun-time,and also the apparent right ascension and dec lination of the sun.

If, however, it is desired to use my apparatus for ascertaining the sunsright ascension and declination, or the equation of time for any otherday, the set-screwy must be loosened, an d the shaft h, or earths axis,rotated until the pointer t" indicates the day required on theeclipticcircle F. Then the watch 0 will indicate in hours, minutes, andseconds the suns right ascensionas, for instance, on 25th June the watch0 will read 6 hours, 15 minutes, 15 seconds, and the declinationindicated on the meridian-strip h will read 23 ,44, north, while thedifference between the time indicated by the clock A and the point onthe equatorial circle intersected between the meridian ot' the placeforwhich the instrument is set will be two minutes and seventeen seconds,showing the sun to be that much slow.

If it is desired to ascertain what time the sun rises and sets on anyday of the year at any given place, the apparatus must be set for thatday and place, as before described. Then turn the terrestrial globe Euntil the place is brought directly under the circular strip 20. Thenfollow the meridian of the place to the equator, and at the pointcoinciding therewith on the equatorial circle will be read the time atwhich the sun rises at that place.

To ascertain the time of sunset on the same day, the globe is thenturned from west to east until the place of observation is broughtdirectly under the strip 20 on the opposite side of the instrument, andthen, by following the meridian of that place to the equator, we find,coinciding with that point on the equatorial circle, the hour of sunset.

It may be observed, however, that if the time of sunrise is ascertained,the time of sunset on the same day is readily learned by subtracting thetime of sunrise from twelve hours, the remainder being the time ofsunset.

Having thus described myimproved apparatus, What I claim as myinvention, and desire to secure by Letters Patent, is-

1. The combination and arrangement of a clock-movement with aterrestrial globe and sun-sphere, and intermediate gearing, whereby theterrestrial globe is capable of a diurnal revolution on its axis, andthe sun-sphere of an annual revolution around it, substantially asdescribed.

2. The combination of a terrestrial globe capable of a diurnal movementon its axis with a graduated equatorial circle capable of an annualrotation around it in the plane of the equator of the globe,substantially as described.

3. In combination with'a terrestrial globe capable of a diurnal movementon its axis, an equatorial circle capable of an annual revolution aroundthe terrestrial globe in the plane of its equator by means of acog-wheel having a uniform movement gearing into teeth so arrangedaround the periphery of the equatorial circle as to give it a slowermovement during one half of its revolution than during the other half,substantially as and for the purpose described.

4. In combination with a terrestrial globe capable of a diurnal motionon its axis, and an equatorial circle capable of an annual revolutionaround the terrestrial globe in the plane of its equator, a circularstrip nearly surrounding the globe at right angles to the plane of theecliptic, with a semicircular are attached to said strip and parallel tothe surface of the globe in the plane of the ecliptic, and revolvin gwith the equatorial circle by means of pins projecting therefrom,substantially as and for the purpose set forth.

5. In combination with a terrestrial globe capable of a diurnalrevolution on its own axis, a sun-wheel having an annual rotation on itsaxis, and adapted to carry a sphere representing the sun, the axis ofrevolution of the sun wheel being set at a suitable angle to the axis ofthe terrestrial globe, corresponding to the angle between the equatorand the ecliptic, and also intersecting the center of the terrestrialglobe, substantially as and for the purpose described.

6. In combination with a terrestrial globe capable of diurnal rotationon its axis, a sunwheel capable of annual revolution, its axis by meansof suitable intermediate gearing from the shaft of the axis of the globemeshing into teeth so arranged on the periphery of the sunwheel as tocause it to move more slowly during one half of its revolution than itdoes during the other half, substantially as and for the purposedescribed.

7. In combination with a terrestrial globe capable of diurnal rotationon its own axis, and a sun-wheel capable of annual revolution on itsaxis in a plane parallel to that of the ecliptic,-as hereinbeforedescribed, a stationary ecliptic-circle graduated with the days of theyear, and set in the same plane and with the same center as thesun-wheel, substantially as and for the purpose hereinbefore described.

8. In combination with the subject-matter of the preceding claim, astationary zodiacal circle set in the same plane and with the samecenter as the sun-wheel, substantially as and for the purpose described.

.9. In combination with a terrestrial globe capable of diurnalrevolution on its axis, a watch-movement so connected, substantially ashereinbefore described, by suitable gearing with the shaft giving motionto the globe as to indicate on the watch-dial, in hours and theirsubdivisions, the suns apparent right ascension, substantially asdescribed.

10. The combination of a terrestrial globe capable of diurnal rotationon its axis, a graduated equatorial circle having coincident axis ofrotation therewith, and capable of annual rotation around the globe, asun-wheel having an axis of rotation parallel to the plane of theecliptic and capable of annual rotation, a sunsphere attached to thesui'i-wheel. and revolving therewith, a stationary equatorial circle,

graduated for the days of the year, having the same plane and center ofrevolution as the sunwheel, and an index attached to the sun-wheel toindicate the days of the year, the whole being connected together bysuitable gearing to give the proper relative motion o the parts, anddetachably connected with the clock or prime motor, so as either to workantomatically or to be set and rotated by hand at pleasure,substantially as and for the purposes hereinbefore described.

In testimony whereof I, the said JAMES F. SARRATT, have hereunto set myhand.

JAMES F. SAItItATT. Witnesses:

JNo. K. SMITH, O. E. MILLIKEN.

